Local bubble distribution in bubbly turbulent Taylor-Couette flow

ORAL

Abstract

In turbulent Taylor-Couette flow, the injection of bubbles reduces the global drag on the cylinder surfaces. The previous bubbly turbulent drag reduction measurements in TC flow were mainly based on the global torque, which is not sufficient to understand the mechanism of bubbly drag reduction. One of the key issues is the actual bubble distribution inside the TC gap. Using optical fibers placed inside the TC gap, we scanned the local bubble distribution in the radial direction. An extension of this technique is a four-point optical fiber probe, which enables to retrieve the bubble velocity vector and aspect ratio.

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Authors

  • Daniela Narezo

    University of Twente

  • Dennis van Gils

    University of Twente

  • Chao Sun

    The University of Twente, University of Twente, Physics of Fluids group, University of Twente, University of Twente, The Netherlands, Physics of Fluids Group, University of Twente

  • Detlef Lohse

    The University of Twente, University of Twente, Physics of Fluids group, University of Twente, Physics of Fluids, Twente University, The Netherlands, University of Twente, The Netherlands, Physics of Fluids, University of Twente, Physics of Fluids Group, University of Twente